A deployable tail unit as described in German Pat. No. 3,026,409 has wings each constituted as a textile two-wall cover and a partially telescoping strut arrangement that erects it. The strut arrangement is formed of a plurality of parts which take up a relatively large space within the missile and therefore constitute a considerable portion of lost space, and the construction of these parts is fairly expensive. In addition the deployment of the wing is problematic in view of the high acceleration forces created when the aircraft in question is fired or launched.
A fold-down wing is known which is a simple flap that folds against the side of the aircraft and that is erected by a spring when the projectile is launched, typically when it exits the barrel of the cannon from which it is fired. The wings are, however, invariably relatively flimsy and this lack of rigidity reduces their aerodynamic effectiveness.
Another disadvantage of the known wings is that they are unable to impart spin to the vehicles because they are not rigid enough to withstand the angular forces created in such a situation.